To directly answer your question Xithor, WKC is built as a single player RPG and an online mission/quest based RPG. You take your efforts and work from single player into the online part. But it is a fully fleshed out part of the game and is truly online and not simulated like the .hack series. You will actually play with other players across the world. Which in our case is you play with I think everyone but Japan or whoever it was got the International version.

At this late stage I would recommend just waiting until WKC2 comes out and buying that since you'll be getting a new game and an improved old game as one. If you want you can buy the original for probably a low price, but the community is going to be transitioning over in the coming months to the new game. So waiting is probably the best, unless you're in the EU territories then you don't have to wait. ^^ But it is definitely worth playing. The single player story is a little weak, but the online stuff is a lot of fun and you can play with friends or just strangers. It has that same sort of Monster Hunter addictive quality to it. And they rebalanced everything in WKC2, so they took out a lot of that grind that Fate was talking about.

And you should stop on by Fate. I've been on a lot lately working to getting GR15 myself. But we do play on Sundays as a group.